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Tutorial Mac Won’t Boot? A Step-By-Step Guide to Waking It Up

Discussion in 'Linux Distributions' started by La Freak, Mar 5, 2015.

  1. La Freak

    La Freak Support Team Staff Member Support Team


    Last month my dad brought home a 2011 MacBook Pro that his work didn’t want because the battery wouldn’t charge. Plugged in, it worked for about a week, then it simply stopped booting. He said, if we could get it to work, we would keep it.

    The following article documents my tale from the trenches in trying to bring a Mac to life.

    Though I ultimately failed to bring it to working condition for reasons I will get into later, I hope this story and instructions can be of use to someone else out there trying to revive a Mac.

    First things first: Check that the computer has power. Is the battery plugged in properly, or is it plugged into the wall properly, with all parts of the cable secure? It might sound obvious, but before you can move on to any of the other strategies on this list, you have to know the state of your Mac’s power.

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    If you’re lucky, you just found out that your Mac wasn’t powered, and fixed the connection. It turns on, and you get to stop reading this article and do something more fun.

    Not so lucky? Keep reading.

    Power Cycle
    I have to give credit to Victor Clausson from iFixit Answers for sharing this technique I have seen nowhere else, which managed to awaken my Mac when it showed no signs of life. At the time, my MacBook was not responding to the power button at all, and not charging, despite being plugged in and showing a glowing green light on the MagSafe power cable indicator.

    This special power cycle takes about 20 seconds:

    1. Unplug the battery.
    2. Unplug the MagSafe power cable.
    3. Hold down the power button for about 10 seconds and continue to do that.
    4. While still holding the power button down, insert the MagSafe power cable and hold it for another 10 sec.
    5. Release the power button after those 10 sec and make a “normal” press as if you would normally turn on your computer.
    When I tried that, the Mac woke up, showed the loading screen, and played the start-up chime. It gave me brief hope that everything would be okay, but my MacBook quit before it finished booting, suggesting other problems. If you’re facing a similar situation where your Mac starts to turn on but runs into problems during boot-up, read on.

    Reset Your SMC & PRAM
    My next course of action, now that I could get the Mac to wake up, was toreset the SMC and PRAM.

    Your Mac’s SMC (System Management Controller) controls its lights, fans, displays, power, and more. That’s why when my Macbook Pro didn’t boot, the first thing I did after a power cycle was reset the SMC.

    If you own a recent MacBook without a removable battery (like the MacBook Air or Retina MacBook Pro) the steps to reset your SMC are as follows:

    1. Shut down your MacBook.
    2. Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
    3. On the built-in keyboard, press the (left side) shift+control+option keys and the power button at the same time.
    4. Release all the keys and the power button at the same time.
    5. Press the power button as normal to turn on the computer.
    On a portable Mac with a removable battery (like the older MacBook Pro), the instructions are as follows:

    1. Disconnect the MagSafe power adapter from the computer, if it’s connected.
    2. Remove the battery.
    3. Press and hold the power button for 5 seconds.
    4. Release the power button.
    5. Reconnect the battery and MagSafe power adapter.
    6. Press the power button to turn on the computer.
    For instructions for older MacBooks without removable batteries (All editions of MacBook Air, and 2009 MacBooks and MacBook Pros), and the Mac Pro, Intel-based iMac, Intel-based Mac mini, or Intel-based Xserve, refer to Apple Support’s System Management Controller reset instructions.

    I reset the PRAM (parameter random-access memory) too while I was at it, though I don’t think it directly affects power.

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    To reset the PRAM, turn on your Mac and immediately after you hear the start-up chime, hold down the command+option+p+r keys, and continue holding until the computer restarts a second time. More modern MacBooks store the information that PRAM used to in NVRAM (non-volatile random-access memory), which is reset in the same way.

    We covered the different ways to reset your SMC and PRAM depending on what kind of Mac you are using. They’re all quick, taking less than a minute.

    Run Apple Diagnostics/Hardware Test
    One neat thing about owning a Mac (I’m usually a Windows user) is that Apple provides its own Hardware Test (called Apple Diagnostics from mid-2013 onwards). It runs in its own bare-bones operating system, without the need to have the main operating system working.

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    The test is usually already on the Mac, but if you updated your operating system or had to re-install your operating system for any reason, they might not be loaded yet. Here’s where it gets more impressive: your Mac can actually connect to the Internet while the main operating system isn’t working, and automatically, magically, download the Apple Diagnostics/Hardware Test. I was floored.

    To access the Apple Diagnostics/Hardware Test:

    1. Press the Power button to start up your Mac.
    2. Hold option+d keys immediately after the Apple startup chime until you see a “Starting Internet Recovery” message. You may be asked to select your WiFi network.
    3. Give your Mac some time to download the tests.
    4. Finalise installation when the tool asks you to select your language.
    Once the Apple Diagnostics/Hardware is set up, go to the Hardware Tests tab and click on the big Test button. Extended testing checks RAM (Random Access Memory), one of the essential elements of every computer, among other things. It took me 45 minutes, but it can take longer depending on how much RAM you have installed. That’s why I recommend you run the standard test first, to save yourself some time.

    Run Memtest
    Unfortunately, Apple’s Hardware Tests are often considered inadequate for diagnosing RAM problems completely. MacRumors’ guide to Testing RAM recommends Memtest, a popular memory testing tool typically run from Terminal. There are free and paid options, and even a graphical user interface (GUI) version.

    Run Memtest in Safe Mode, a version of your operating system that does some checks and prevents unnecessary software from running.

    Starting Your Mac in Safe Mode
    1. Press the Power button to start up your Mac.
    2. Hold the shift key immediately after you hear the start-up chime.
    3. Release the Shift key when you see the Apple logo appear on the screen.
    If you discover a problem with your Mac’s RAM and you are able to open it, you might be able to switch the faulty memory or simply remove it (in case not all of your RAM is bad).

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    Recovery Partition
    OS X provides a suite of tools to recover your Mac’s operating system calledOS X Recovery. You can access Recovery Mode by holding downcommand+r immediately after you hear the start-up chime. After the Apple logo appears, you can release the keys and you will see a screen giving you options to:

    • Restore your Mac from a Time Machine backup.
    • Verify and repair connected drives using Disk Utility.
    • Check your Internet connection or get help online using Safari.
    • Install or re-install OS X.
    We suggest you first use Disk Utility to verify that your start-up disk doesn’t have problems (although repair will check for problems and fix any it finds, so that may be more efficient). If that doesn’t help, try restoring from a recent Time Machine backup. As a last-resort, try a full re-install.

    For those of you reading this article pre-emptively (lucky you!), consider this your one reminder to backup your data. Do it – it’s easy and worth it (trust me, speaking from experience). Don’t procrastinate backing up until you have a problem.

    Run Linux
    If you need something to work on your Mac in between getting a repair or replacement, you could also try running Linux off of a USB or CD. That may keep you going for a while, though I have a feeling you’ll want to get back to your regular operating system as soon as possible.

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    What You Should Know About Boot Errors
    Unusual visual and auditory behaviour may be error code indicators. A common audio error code, for example, is three beeps in a row followed by a pause, repeating. That indicates that your RAM did not pass a data integrity check.

    In the event that none of your efforts to revive your Mac come to fruition, pay attention to the symptoms and consider contacting an Apple Support person.

    As for me, my quest to bring a Mac back to life ended when it became clear that it had a broken battery, bad RAM, and a bad hard drive. We felt it would be too expensive to replace all the parts for a Mac that was destined for disposal in the first place.
    derx likes this.
  2. derx

    derx El Vampiro Staff Member Moderator

    Ah ganun pala yun. hehehehe... Thank you boss La Freak :geek: (y) :cat:
  3. La Freak

    La Freak Support Team Staff Member Support Team

  4. thanks for the tips especially the power cycle thingy (y)
  5. maiapply nga, tnx dito boss..
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